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排序方式: 共有620条查询结果,搜索用时 31 毫秒
31.
Swinnen SP Puttemans V Vangheluwe S Wenderoth N Levin O Dounskaia N 《Behavioural brain research》2003,139(1-2):177-195
The role of afferent information in bimanual directional interference was studied by means of a modulation of the response-produced information in one of both limbs. In Experiment 1, visual information was either present, withdrawn, or shown with a directional transformation on a LCD screen. In Experiment 2, the technique of muscle tendon vibration was used to bias the kinesthetic afferent information associated with movement. The findings revealed strong evidence for directional interference between both limbs. Nevertheless, no evidence could be advanced that the observed interference from the right onto the left limb movement was modulated by manipulation of the afferent sources of information. It is concluded that directional interference primarily emerges at the efferent level of movement planning and organization. 相似文献
32.
Slowness is a common complaint in children with attention-deficit hyperactivity disorder (ADHD) and with developmental right hemisphere syndrome. However, it was our clinical impression that slowness in developmental right hemisphere syndrome was more prominent than in ADHD. Our objective was to assess slowness as operationalized by speed of performance in children with developmental right hemisphere syndrome, children with ADHD, and controls. The research sample comprised 19 children in each group, matched for age, gender, socioeconomic status, IQ, and handedness. The subjects were administered a reaction time battery assessing speed of performance. Overall, the average performance differed among the three study groups (F(2,53) = 2.40, P < .01). Children with developmental right hemisphere syndrome were slower than their peers with ADHD (t(35) = 1.99, P < .05) and slower than controls (t(35) = 4.55, P < .001). Children with ADHD performed more slowly than controls, although for the majority of tasks, this was nonsignificant. We conclude that slowness is an integral and consistent component of developmental right hemisphere syndrome and cannot be attributed only to the ADHD symptomatology. 相似文献
33.
OBJECTIVES: To compare lower limb joint torques during sit-to-stand in normal elderly subjects and people with Parkinson's disease, using a developed biomechanical model simulating all phases of sit-to-stand.Design. A cross-sectional study utilizing a Parkinsonian and a control group. BACKGROUND: Subjects with Parkinson's disease were observed to experience difficulty in performing sit-to-stand. The developed model was used to calculate the lower limb joint torques in normal elderly subjects and subjects with Parkinson's disease, to delineate possible causes underlying difficulties in initiating sit-to-stand task. METHODS: Six normal elderly subjects and seven age-matched subjects with Parkinson's disease performed five sit-to-stand trials at their self-selected speed. Anthropometric data, two-dimensional kinematic and foot-ground and thigh-chair reactive forces were used to calculate, via inverse dynamics, the joint torques during sit-to-stand in both before and after seat-off phases. The difference between the control and Parkinson's disease group was analysed using independent t-tests. RESULTS: Both control and Parkinson's disease groups had a similar joint kinematic pattern, although the Parkinson's disease group demonstrated a slower angular displacement. The latter subjects produced significantly smaller normalized hip flexion torque and presented a slower torque build-up rate than the able-bodied subjects (P<0.05). CONCLUSION: Slowness of sit-to-stand in people with Parkinson's disease could be due to a reduced hip flexion joint torque and a prolonged rate of torque production. 相似文献
34.
The enzymatic activity of creatine phosphokinase and the lysosomal enzymes cathepsin D and acid phosphatase was followed during skeletal muscle regeneration after partial excision to the gastrocnemius muscle in the rat. For each time interval (1, 2, 5, 14 and 45 days) following injury, the activity of the regenerated muscle was compared with the activity in the contralateral sham operated muscle. The specific activity of creatine phosphokinase of the regenerated muscle showed a significant decrease (25%) during the first 2 days post injury and thereafter was comparable to that of the uninjured control muscle. The activity of cathepsin D was 2.3-4-fold significantly higher in the regenerated muscle than in the control intact muscle from day 1 until day 14 post-injury. At 45 days after partial excision, the activity of this enzyme was comparable to a normal muscle. However, the activity of another lysosomal enzyme (acid phosphatase) did not show any distinct changes from the level of this enzyme in the uninjured muscle during the course of muscle regeneration. It is suggested that elevation of lysosomal enzymes in skeletal muscle may not be confined to conditions of muscle wasting and degradation but also to differentiation and development processes such as during muscle regeneration following injury. 相似文献
35.
After injury of their axons, damaged neurons shift their metabolic activity into a reparative mode aimed at survival and regeneration or, alternatively, they undergo degeneration and die. Previous reports have shown that at the initial stages of the response to axonal injury, polyamines are essential for neuronal survival and can accelerate functional recovery. In this study we examined the ability of exogenous polyamines to accelerate regeneration following crush of the pre- or postganglionic sympathetic nerves of the superior cervical ganglion in adult rats. We found that early treatment with polyamines after pre- or postganglionic nerve crush, accelerated the reappearance of choline acetyltransferase activity in the superior cervical ganglion, and of [3H]norepinephrine uptake in the iris, respectively. Functional recovery from eyelid ptosis was also accelerated. We conclude that treatment with polyamines can enhance regeneration of peripheral sympathetic neurons. 相似文献
36.
O Merimsky I Meller J Issakov Y Kollender D Oron G Flusser M Gutman D Lev-Chelouche M Inbar 《Oncology reports》1999,6(4):913-920
Chemotherapeutic cytoreduction of soft tissue sarcomas may permit less radical operation. In cases of large or multi-compartmental masses, deeply seated tumors or involvement of a neurovascular bundle, down-sizing of the mass is required before limb sparing surgery can be considered. We have applied a combination chemotherapy consisting of intravenous adriamycin and ifosfamide with intra-arterial cisplatin for patients with soft tissue sarcomas of the extremity as induction treatment, and switched to an intravenous-only protocol due to toxicity and management difficulties. Adjuvant chemotherapy and radiation therapy were given after limb-sparing surgery in both regimens. Fresh tumor specimens were obtained and were examined for tumor size, surgical margins, percent of necrosis, evidence of vascular or perineural invasion, and the presence of Pgp, Ki-67, p53, PCNA and bcl-2-oncoprotein. Our results in terms of percentage of tumor necrosis were comparable and even better in favor of the second regimen [38% good histological response with intravenous (i.v.)-only versus 12.5% for combined i.v. + intra-arterial (i.a.]. The clinical and radiological responses were also better for the second (i.v. only) regimen (45%) than for the first (i.v. + i.a.) regimen (12.5%). The toxicity and the inconvenience to the patients and to the treating staff were greater in the first regimen that combined intra-arterial and intravenous infusions. In the first group the failure rate is 75% within 32 months of follow-up, while it is 33% within 12 months follow-up in the second group. The immunohistochemical markers did not correlate with disease control nor with the patient outcome. Intravenous administration of ADR-IFX induction chemotherapy was more feasible than combined i.v. ADR-IFX plus i.a. cisplatin and achieved better results. 相似文献
37.
Yuval Shilon Yehuda Pollak Fortu Benarroch Varda Gross-Tsur 《European journal of paediatric neurology》2008,12(5):398-400
BACKGROUND: Tourette syndrome (TS) is a chronic disorder characterized by motor and vocal tics. Previous studies reported a substantial lag period between disease onset and diagnosis ranging from 3 to 11.9 years. AIMS: To determine the lag period and factors associated with diagnosis delay of TS. METHODS: All files of 185 children with TS attending one neuropediatric unit in Jerusalem were reviewed. Lag time between disease onset, according to DSM criteria, and diagnosis was determined and the contributions of the disease course, comorbidities and epidemiological factors were assessed. RESULTS: A relatively short lag to diagnosis following the onset of diagnosable TS was documented (mean 13.2+/-15.9 months, median 6 months). A relatively longer gap was associated with older age at TS onset (r=0.161, p<0.05) and vocal tics as the first manifestation rather than motor or combined motor and vocal tics (mean=20.3+16.3 months vs 11.9+16.5 and 12.6+15.2, respectively, p<0.05). A relatively shorter gap was associated with tic severity (r=0.13, p<0.05) and presence of comorbid obsessive-compulsive disorder (OCD) (9.5+14.7 months vs. 14.1+16 without OCD, p<0.05). CONCLUSIONS: Lag time to diagnosis is relatively short in our population. Factors associated with a shorter lag (early age of TS onset, motor tics as the first manifestation, greater tics severity and the presence of OCD) may be perceived as disruptive, prompting patient and families to seek medical care. Conversely, vocal tics as the first manifestation, associated with a longer lag, may be misdiagnosed as features of common pediatric conditions, thus delaying diagnosis. 相似文献
38.
Heymann AD Shapiro Y Chodick G Shalev V Kokia E Kramer E Shemer J 《Diabetes care》2004,27(11):2581-2584
OBJECTIVE: To assess whether the influenza vaccination of community-dwelling, diabetic, elderly individuals is associated with reduced rates of hospitalization and death. RESEARCH DESIGN AND METHODS: In this outcome-research study, we compared mortality and hospitalization rates of 15,556 patients aged >or=65 years followed using a diabetes registry in a large health maintenance organization to that of 69,097 members not suffering from chronic disease who were considered as a reference group. The study outcomes included all-cause death and hospitalization in internal medicine or geriatric wards for any reason over winter and summer (control) periods. RESULTS: Vaccination rates were 48.8 and 42.0% among patients with diabetes and the reference population, respectively. Influenza vaccination was associated with a 12.3% reduction in hospitalization rates for patients with diabetes compared with 23.0% in the reference group (P = 0.08). The reduction in hospitalization rates was similar in both sexes among patients with diabetes. In addition, there was a significant reduction in mortality for the vaccinated group of patients with diabetes when compared with the nonvaccinated group except for female patients aged >or=85 years. CONCLUSIONS: The study results support the use of influenza vaccine among an elderly population. However, there does not appear to be an additional benefit for patients with diabetes. 相似文献
39.
DNA vaccination with CD25 protects rats from adjuvant arthritis and induces an antiergotypic response 总被引:6,自引:0,他引:6
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Mimran A Mor F Carmi P Quintana FJ Rotter V Cohen IR 《The Journal of clinical investigation》2004,113(6):924-932
Ab's to the alpha-chain of the IL-2 receptor (anti-CD25) are used clinically to achieve immunosuppression. Here we investigated the effects of DNA vaccination with the whole CD25 gene on the induction of rat adjuvant arthritis. The DNA vaccine protected the rats and led to a shift in the cytokine profile of T cells responding to disease target antigens from Th1 to Th2. The mechanism of protection was found to involve the induction of an antiergotypic response, rather than the induction of anti-CD25 Ab's. Antiergotypic T cells respond to activation molecules, ergotopes, expressed on syngeneic activated, but not resting, T cells. CD25-derived peptides function as ergotopes that can be recognized by the antiergotypic T cells. Antiergotypic T cells taken from control sick rats did not proliferate against activated T cells and secreted mainly IFN-gamma. In contrast, antiergotypic cells from CD25-DNA-protected rats proliferated against activated T cells and secreted mainly IL-10. Protective antiergotypic T cells were found in both the CD4+ and CD8+ populations and expressed alpha/beta or gamma/delta T cell receptors. Antiergotypic alpha/beta T cells were MHC restricted, while gamma/delta T cells were MHC independent. Thus, CD25 DNA vaccination may induce protection from autoimmunity by inducing a cytokine shift in both the antiergotypic response and the response to the antigens targeted in the disease. 相似文献
40.
A preliminary investigation into light-modulated replication of nanobacteria and heart disease 总被引:6,自引:0,他引:6
Sommer AP Oron U Pretorius AM McKay DS Ciftcioglu N Mester AR Kajander EO Whelan HT 《Journal of clinical laser medicine & surgery》2003,21(4):231-235
OBJECTIVE: The purpose of this preliminary study is to evaluate the effect of various wavelengths of light on nanobacteria (NB). BACKGROUND DATA: NB and mitochondria use light for biological processes. NB have been described as multifunctional primordial nanovesicles with the potential to utilize solar energy for replication. NB produce slime, a process common to living bacteria. Slime release is an evolutionary important stress-dependent phenomenon increasing the survival chance of individual bacteria in a colony. In the cardiovascular system, stress-induced bacterial colony formation may lead to a deposition of plaque. METHODS: Cultured NB were irradiated with NASA-LEDs at different wavelengths of light: 670, 728 and 880 nm. Light intensities were about 500k Wm(-2), and energy density was 1 x 10(4) J m(-2). RESULTS: Monochromatic light clearly affected replication of NB. Maximum replication was achieved at 670 nm. CONCLUSIONS: The results indicate that suitable wavelengths of light could be instrumental in elevating the vitality level of NB, preventing the production of NB-mediated slime, and simultaneously increasing the vitality level of mitochondria. The finding could stimulate the design of cooperative therapy concepts that could reduce death caused by myocardial infarcts. 相似文献